When taken with its neighbor Mount Meeker, they are sometimes referred to as the Twin Peaks (not to be confused with a nearby mountain called Twin Sisters).

As the only fourteener in Rocky Mountain National Park, the peak has long been of interest to climbers. The easiest route is not "technical" during the summer season, and was probably first used by American Indians collecting eagle feathers, but the first recorded ascent was in 1868 by the surveying party of John Wesley Powell. The East Face of the mountain is quite steep, and is surmounted by a gigantic sheer cliff known as "The Diamond" (so-named because of its shape, approximately that of a cut diamond seen from the side and inverted - see image at right). Another famous profile belongs to Longs Peak: to the southeast of the summit is a series of rises which, when viewed from the northeast, resembles a beaver. The photo shows the beaver climbing the south (left side) of the mountain.

The first proposal to climb the Diamond, in 1954, was met with an official closure by the National Park Service, a stance not changed until 1960. The Diamond was first ascended by Dave Rearick and Bob Kamps that year, and the route was listed in Allen Steck and Steve Roper's influential book Fifty Classic Climbs of North America. The easiest route on the face, the "Casual Route" (5.10-), was climbed many years later and became the most popular route up the wall.

Mills Glacier

Longs Peak has one glacier named Mills Glacier. The glacier is located around 12,800 feet (3,900 m) at the base of the Eastern Face, just above Chasm Lake. There is also another permanent snowfield, called The Dove, located north of Longs Peak. Longs Peak is one of less than 50 mountains in Colorado that has a glacier.

Hiking Longs Peak

No technical climbing is required to reach the summit of Longs Peak during the summer season, which typically runs from mid July through early September. Outside of this window the popular "Keyhole" route is still open, however its rating is upgraded to "technical" as treacherous ice formation and snow fall necessitates the use of specialized climbing equipment including, at a minimum, crampons and an ice axe. It is considered to be the most difficult 3rd class fourteener in Colorado. Those intending to summit would be advised to read the National Park Service guide linked below for tips on proper preparation and equipment to bring. Another helpful resource is Paul Nesbit's Longs Peak: Its Story and a Climbing Guide released in a new 11th edition in 2005 (edited by Stan Adamson, Broomfield, Colorado: Grey Wolf Books U.S.A.).

While the climb is non-technical it is by no means easy or without serious danger. The climbing trail past the Keyhole presents dramatic, sweeping vistas that can feel a bit exposed. Due care is advised on the Ledges - inexperienced climbers have fallen to their deaths in this portion of the climb. The Trough is difficult physically and is the last real attempt of the mountain to turn around those unworthy of the Summit. Rock fall caused by other climbers is a real concern in the Trough - Stay Alert. Warn others if you kick out a rock by shouting, "ROCK." To move successfully through the Trough, break it down into a series of small climbs and rest periodically. The Chockstone that separates access from the Trough to the Narrows remains problematic. Access the Narrows by going to the left of the Chockstone and climb over the obstacle. Descend via the other side of the Chockstone when returning to the Trough from the Narrows. The Narrows have seen some thinning of the ledge/trail over the past decade. This is primarily due to natural erosion of the granite from the natural freezing/thawing process. Access from the Narrows to the Homestretch has also become more difficult over the past decade due to this erosion process. Rockfall now blocks an old, wide portion of the narrows that gave access to the Homestretch. Climbers will now have to negotiate an approximate twenty-foot pitch of Class III climbing to enter the Homestretch. This pitch can be taxing due to the 14,000' elevation.

The hike from the trailhead to the summit is 7.5 miles (12 km) each way. Most hikers begin before dawn in order to reach the summit and return below the tree line before frequent afternoon thunderstorms bring a risk of lightning strikes. The most difficult portion of the hike begins at the Boulder Field, 5.9 miles (9.5 km) into the hike. After scrambling over the boulders, hikers reach the Keyhole at 6.2 miles (10 km).

The following quarter of a mile involves a scramble along narrow ledges, many of which may have sheer cliffs of 1,000 feet (305 m) or more just off the edge. The next portion of the hike includes climbing over 1,000 vertical feet (305 m) up the Trough before reaching the most exposed section of the hike, the Narrows. Just beyond the Narrows, the Notch signifies the beginning of the Homestretch to the football field-sized, flat summit. It is possible to camp out overnight in the Boulder Field (permit required) which makes for a less arduous two day hike, although this is fairly exposed to the elements. Over 55 people have died climbing Longs Peak. According to the National Park Service, one person, on average, dies every year attempting to climb the mountain. In the summer of 2005 a Japanese climber was blown off a ledge after reaching the summit. On September 3, 2006 a man fell 800 feet (244 m) to his death when some rocks let go while he was descending the loft route.

For hikers who do not wish to climb to the summit, there are less-involved hikes on the peak as well. Peacock Pool and Chasm Lake are popular hiking destinations and follow well-maintained trails. It is also rewarding to hike just to the Boulder Field, the Keyhole, or the seldom-visited but spectacular Chasm View. Camping is available at the Boulder Field and also on the lower portions of the mountain, such as Goblin's Forest. Technical climbers, with the correct permit, are allowed to use "bivy" sites at the base of the East Face and at Chasm View. It is also possible to camp to the South of the mountain at Sand Beach Lake.

Climbing Longs Peak

In addition to the standard "Keyhole" route, there are more serious and more technical climbs on Longs Peak. Climbers should seek qualified instruction; deaths on Longs Peak are an annual occurrence. Some of the more common routes are, in approximate order of popularity,

North Face Cables route. This follows the Keyhole route to the Boulder Field, then ascends the North Face of the peak. It requires one or two pitches of low-5th class climbing, and is often downclimbed or rappelled by technical climbers since it is one of the fastest ways to ascend or descend the peak. In the early 20th century, enterprising guides installed a series of large steel eye bolts along this route, connecting them with a steel cable similar to systems in the Alps. The cables were removed later due to the lightning hazard, but the bolts remain and are used as rappel anchors.

Kieners Route. A traditional mountaineering climb that involves a climb of Lambs Slide, which is icy later in the season, then an exposed traverse of the Broadway ledge, and then low-5th class climbing. Lambs Slide is so-named because of the Reverend Elkanah J. Lamb's nearly fatal tumble down it The most recent fatal tumble was November, 2006.

via the Loft. The Loft is the semi-permanent snowfield between Longs Peak and its south-eastern neighbor Mt. Meeker. From the saddle you can traverse to either peak. One such traverse route is Gorilla's Traverse. It is also possible to ascend to the saddle via Lambs Slide.

via the East Face. The East Face is the steep, 1,000 + foot (305 + m) wall that includes the Diamond and the Lower East Face. All climbs here are technical, from 5.10 to 5.13. It is also possible to ascend to the (climber's) left of the Diamond face proper. The routes on the right side of the Diamond are often aid climbed, and may require spending the night on the wall; the rock here can be very wet. Routes on the left side of the Diamond are usually free climbed. Only qualified climbers should attempt climbs on this face, and should take into consideration the effects of altitude and alpine conditions in addition to the difficulty rating.

via the Notch Couloir. This is a technical climb involving rock climbing and, at some times of year, ice climbing. The Notch Couloir is to the (climber's) left of the Diamond face.

Keyhole Ridge (5.6)

Description:

Not on the Diamond, but a great technical route to the summit of Longs Peak. Slightly committing with tricky route finding. We roped up for 5 or so pitches, but other parties may do less or more depending on experience.

Follow the trail through the Boulderfield to the Keyhole. The route follows the ridge from the Keyhole to the summit.

From the hut at the Keyhole, hike south up the ramp on the east face until below the False Keyhole, and then head straight up (possibly roping up), to the hiker warning sign. From here, the route finding is slightly tricky, and there are a couple different ways to go. We headed south across the east face of the obvious tower for a pitch, and from there headed straight up dirty rock (5.6) to the summit of the tower. From the top, we dropped down the backside about 10 feet to an obvious ledge, and followed it south. Be very careful as there is much loose rock and the hiking trail is below.

Follow the ledge to the obvious notch before the next large tower. Scramble south up the obvious ramp, and then break left and head south on narrow ledges across the east face of the tower. At a right facing corner (possible fixed pin), head straight up the face following the path of least resistance (5.6). This is another possibly tricky route finding section. Once you reach an obvious ledge system near the crest, continue working south on the east side. Cross to the west side at a notch, and work your way up onto the summit ridge, and follow it to the top.

Protection:
Standard Rack

via one of the snowfields above the Boulder Field. Sometimes referred to as the "doves". This is also a low-5th class climb.

via Keplinger's Couloir, aka Keplinger's Route. This is a long route on the South of the mountain. You do not start at the usual trailhead, but instead from the trailhead to the South, taking the trail to Sand Beach Lake and continuing cross-country from there; good routefinding is essential here. The route continues up the south side of the mountain until it joins the Keyhole Route at the Homestretch which is the technical crux (class 2+ or 3).

via the Trough Couloir. This also starts from a different trailhead to the North, and is also long. It may be ascended in summer, but there will be rock fall from the many climbers high above on the Keyhole route. It is better done when full of snow. You do not start at the usual trailhead, but instead starts at Glacier Gorge TH to the NW.

via Camel's Gully. This is used mainly as a descent route after climbing the East Face. It ascends from Mills Glacier to the saddle between Mt. Lady Washington and Longs Peak.

via the North Face. Follow the Keyhole route past the Keyhole and around to the North Face. Many lines have been climbed, all technical, but these routes are seldom done. The rock quality is not high, and the Keyhole route is below, so some of these routes present rock fall danger to other climbers.

There are also technical climbing routes that do not lead to the summit. These include climbs on the Lower East Face, such as Stettner's Ledges, climbs on Chasm View Wall, climbs on the Prow and climbs on the Palisades. In addition, Mt. Meeker has some ice couloirs, most notably "Dreamweaver."

Running or jogging the first few miles of Longs Peak is also popular. Fort Collins High School Cross Country team may be seen occasionally on summer mornings pounding up the mountain past the hikers